Method and apparatus for transporting gas



Sept. 29, 1970 'r. MGCUTCHAN 3,531,064

METHOD AND APPARATUS FOR TRANSPORTING GAS Filed April 12, 1968 2 Sheets-Sheet 1 INVENTOR.

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Sept. 29, 1970 B. T. M CUTCHAN METHOD AND APPARATUS FOR TRANSPORTING GAS Filed April 12, 1968 2 Sheets-Sheet 2 FILE 1% I N VEN T OR. 82005 77 Mt Cara 441 United States Patent O 3,531,064 METHOD AND APPARATUS FOR TRANSPORTING GAS Bruce T. McCutchan, 200 Valley High Road, Burnsville, Minn. 55378 Filed Apr. 12, 1968, Ser. No. 721,032 Int. Cl. B64b 1/40, 1/62 US. Cl. 244-31 Claims ABSTRACT OF THE DISCLOSURE A light weight flexible bag used to collect and transport natural gas to a location for use or storage. The gas pressure inside the bag is regulated by a temperature control unit having a barometric control valve used to stabilize the pressure of the gas during periods of low external energy. The temperature control unit also functions as a ballast to control the flight elevation of the bag. A pump connected to a gas collecting ring operates to withdraw the gas from the bag.

BACKGROUND OF THE INVENTION Relatively inflexible and costly pipeline systems are presently used to transport natural gas from a source of supply to the consumer. The high cost of gas pipeline systems requires that the lines be continuously used for maximum efficiency with the result that the supply sources are over used and becoming depleted. To hedge against short supply, distributors store gas in tanks under pressure or in rock domes under the earth. The pipeline is not feasible for use to transport gas from smaller remote gas fields large distances to the consumer.

The method and apparatus for transporting gas of the present invention is a flexible and relatively inexpensive system for transporting gas long distances from a source of supply to the consumer in a flexible and efficient manner. Relatively small and remote sources of supply can be efficiently utilized, making gas available to new industrial and population centers. The more economical use of ga supplies will conserve gas reserves.

SUMMARY OF THE INVENTION The invention relates to a method and apparatus for transporting gas, as natural gas and other lighter than air gases. The apparatus is comprised of a large flexible gas impervious bag capable of being transported through the air. Attached to the bottom of the neck of the bag is a temperature control unit operable to regulate the temperature and pressure of the gas in the bag and to function as a ballast for the bag. The bag is used in conjunction with a loading station where the bag may be filled with gas through an inlet passage leading to the neck of the bag. The gas is removed from the bag through the use of a pump which wtihdraws gas from a gas receiving pipe in communication with the bag.

In the drawings:

FIG. 1 is an elevational view of the apparatus for transporting gas of the invention located on a gas filling and unloading station;

FIG. 2 is an enlarged sectional view taken along the line 2-2 of FIG. 1;

FIG. 3 is an enlarged sectional view taken along the line 3-3 of FIG. 2;

FIG. 4 is a view of the apparatus of the invention being transported in the atmosphere;

station indicated generally at 11. The apparatus 10 comprises a large flexible bag made of gas impervious plastic material as polyethylene and the like. The material is strong and relatively light in weight and may include numerous plastics, rubber, and coated fabric materials. The 'bag 12 has a large spherical shaped body 13 joined to a downwardly tapering neck 14 providing the bag with a generally inverted bulbar shape. For example, bag 12 can be a large thin filrn polyethylene plastic bag of a size to enclose about 7,000,000 cubic feet of gas when fully expanded at atmospheric pressure. A circumferential band 16 reinforces the mid-section of the body 13 and provides a fastening member for a plurality of circumferentially spaced tie-down lines 17 used to hold the apparatus 10 on the station 11. The lower portion of neck 14 has an inlet member or umbilical cord 18 used to provide a passage into the interior of the bag. In filling the bag, inlet hose 19 is connected to the cord 18 so that the gas from the source can be supplied to the bag. When the bag is full as shown in FIG. 3, a closing means 21, as a cord or other fastener, is used to the cord trapping the gas in the bag. The pressure of the gas in the bag is at substantially atmospheric pressure.

The unloading station 11 comprises an annular mound or dike 22 forming a recess or nest 23 in the ground or other support 27. Projected outwardly from the mound 22 are a plurality of anchor rods 24. The tie-down lines 17 are secured to the upper end of the rods 24 to hold the bag on the station 11.

Located centrally in recess 23 is a pit 26 accommodating a temperature control unit indicated generally at 28 mounted on the lower end of neck 14. Control unit 28 has a bowl 29, of metal such as aluminum, closing neck 14. As shown in FIG. 3, the upper edge of bowl 29 has an outwardly and downwardly curved lip 31. The open end of the neck 14 of the bag 12 is attached to the bowl 29 with a flexible O-ring 32. When the neck 14 is in assembled relation with the bowl 29 the O-ring 32 is rolled about the neck 14. The rolled portion of the neck is retained in the annular recess formed by the curved lip 31.

Located within the bowl 29 is a liquid 33, as salt water, oil or similar liquid heavier than air, to provide a ballast for the bag. The temperature of the liquid is controlled by a heating means or burner 34 mounted on the bottom of the bowl 29. Burner 34 has an inlet 36 and discharge flame ports 37 positioned immediately below the bowl 29. Mounted on the side of the burner is a standing pilot 38 to provide a continuous flame for the burner. Both the burner 34 and the pilot 38 are connected to a gas pressure regulator valve indicated generally at 39 which controls the supply of gas from the bag to the burner. A line 41 leads upwardly from the valve 39 to the neck portion of the bag 14 to supply the valve with gas stored in the 'bag.

Referring to FIGS. 2 and 5, the unloading station 11 has a gas receiving pipe or collar 42 mounted in a horizontal position on upwardly projected support rods 43 anchored in a cylindrical base 44 formed from rigid material, as concrete. Collar 42 has a plurality of circumferentially spaced inwardly directed holes 46. As shown in FIG. 5, a pipe 48 connects collar 42 to a valve 49 leading to a pump 51. A motor 52 drives the pump to withdraw gas from the collar 42 and discharge the gas to a discharge line 53 leading to a storage container or a distribution pipe line (not shown).

On operation of pump 51 the gas flow is indicated by arrows 54 in FIG. 2. A reduction of pressure in collar 42 causes the bagto rupture adjacent ports 46 thereby creating openings 47. The gas flows downwardly from the bag 12 through the openings 47 and ports 46 into the collar 42. In this manner theg as is withdrawn from the bag in a continuous manner without the introduction of atmospheric air. With the neck of the bag 14 projected through the opening of collar 42 the pressure of the gas in the bag forces the bag into sealing engagement with the collar 42 so that external air is not drawn into the evacuating system.

Shown in FIG. 4, bag 12 is being towed in the atmosphere by a tow line 55 attached to a power vehicle (now shown), as an airplane, helicopter, blimp or the like. The line 55 may be attached to a powered vehicle on the ground or water such as a truck or ship. An additional line 60 attached to the control unit 28 is used to add ballast and as a retrieving line. The weight of the control unit 28 as well as the shape of the bag 12 maintains the upright flight position of the bag. The burner 34 is operable to maintain the pressure of the gas in the bag by controlling the temperature of the gas in the bag. The burner is automatically operated by operation of the gas regulator valve 39.

As shown in FIG. 6 valve 39 has a first housing 56 with a passage 57 leading to the line 41 connected to the gas source in the bag 12. Joined to housing 56 is a second housing 58 having a passage 59 joined to the inlet member 36 of the burner. A port or hole 61 connects the passages 57 and 59 so that the gas flows through the passages to the burner. A cylindrical valving member 62 located in passage 57 is operable to open and close the port 61. A spring 63 engages the top of the valving member 62 to bias valving member to the closed position against the bottom of housing 56. Secured to and projected downwardly from valving member 62 is a control rod 64 slidably mounted in a casing 66 attached to the lower side of housing 58. Casing 66 has a plurality of holes 67 open to the atmosphere to provide for the free flow of air into and out of the casing 66. Located within casing 66 is a bellows 68 connected to a lever 69 adjustably attached to the control rod 64. A portion of the lever 69 is pivotally mounted on a fulcrum 71. A threaded sleeve 72 adjustably connects the lever 69 to the control rod 64. On rotation of the rod 64 the position of the sleeve along the rod may be changed to adjust the location of the valving member 62 relative to the port 61.

The valve 39 is operable to stabilize the pressure of the gas during periods of low external energy, as at night or an extremely cloudy day. In order to obtain a balance of energy the burner 34 operates to heat the metal dish to increase the temperature of the liquid 33. The liquid 33 functions as a heat exchanging medium to increase the temperature of the gas without the danger of igniting the gas. Bellows 68 is controlled by the ambient or atmospheric pressure. On a decrease pressure the bellows will expand thereby closing the valving member 62 decreasing the flame and burning rate at the discharge ports 37. The burner will not increase the temperature of the liquid. The bag will stay at the flight elevation determined by the atmospheric pressure.

As the apparatus falls the increase in ambient pressure opens the gas valve 39. This supplies gas to the burner heating the liquid 33. The increase in temperature of the gas in the bag will cause the bag to rise thus reduce the pressure on the valve. With the reduction of pressure on the valve the bellows 68 will expand closing the valving member 62. In this manner the flight elevation of a bag will be automatically maintained by the operation of the burner.

Terms of a method of transporting natural gas are included in the invention comprising the steps of initially holding a flexible gas impervious bag 12 in a fixed location and filling the bag with gas. After the bag is filled it is released and allowed to rise in the air against the weight of a ballast comprising the control unit 28 along with the heat transfer liquid 33. The floating bag in flight is moved to an intended designation by a towing vehicle. The bag could be transported mainly by air currents without a towing vehicle by placing the bag in wind patterns of a favorable direction.

The elevation of the bag is automatically regulated by controlling the temperature of the gas in the bag. To increase the elevation of the bag the burner attached to the control unit 28 is ignited heating the heat transfer liquid 33. The result is that the temperature of the gas will be increased in the bag with the result that the altitude of the bag will be increased.

When the bag 12 has reached the intended designation the bag full of gas is lowered to an unloading station 11 where the gas is continuously withdrawn from the bag by the use of a negative or pressure. During the withdrawal of the gas from the bag, the bag is secured to the station.

In use, as shown in FIG. 1, the bag is initially inflated With gas by connecting the supply hose 19 to the inlet cord 18. Since natural gas has a specific gravity of about of that of air the bag 12 will expand to its bulbar shape as shown in FIG. 1. Tie-down lines 17 anchor the bag to station 11. The bag can be expanded in any desired location such as a location which is closed to the source of a remote gas supply.

As shown in FIG. 4, the bag 12 filled with gas may be towed to an intended designation by a powered vehicle. The elevation of the bag is automatically maintained to the operation of the temperature control unit 28. The burner 34 of the control unit is operated to the use of a regulator valve 39 operable in response to changes in the ambient pressure. As the ambient pressure decreases the bellows expand thereby closing the valving member 62. This stops the supply of gas to the inlet 36 of the burner. An increase of ambient pressure opens the valving member 62. Since the pilot 38 is in continuous fluid connection with the supply line 41 the pilot light is on at all times. As soon as gas is supplied to the burner the pilot 38 will ignite the burner heating the bottom of the bowl 29. As the temperature of the heat transfer liquid 33 increases heat is discharged to the gas in the bag 12. The increase in the temperature of the gas in the bag 12 causes the bag to rise thereby maintaining the flight elevation of the apparatus 10.

At the discharge station or unloading station 11 the control apparatus as well as the neck of the bag is lowered through the collar 42 into the pit 26. As shown in FIG. 2, the peripheral portion of the neck 14 is in sealing engagement with the collar 42 preventing the entrance of the atmospheric air into the gas receiving area of the collar. The openings 47 in the bag are created by reducing the pressure in collar 42 sufiicient to rupture the bag to provide passageways from the interior of the bag into the collar 42. Pump 51 operates to remove gas from the bag by a partial vacuum pressure and discharge the gas into a gas discharge line 53. The pump 51 continues to operate until all of the gas has been removed from the bag. As the bag is emptied it folds down over the collar 42 as shown in broken lines in FIG. 2. Thus, the bag as it collapses does not interfere with the pass of the flow of gas from the bag into the collar 42. The bag 12 can be shipped back to the gas source and reused or disposed of at the unloading station.

While there has been shown and described a preferred embodiment and method of transporting gas with a flexible gas impervious bag be it understood that various changes in the bag and temperature control unit may be made by those skilled in the art without departing from the spirit of the invention. The invention is defined in the following claims.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined are as follows:

1. A method of transporting a mass of combustible gas comprising: confining the combustible gas in a large gas impervious bag, allowing the gas confining bag to rise into the atmosphere, heating the gas in the bag with heating means outside the bag operable With gas from the bag to regulate the temperature of the gas in the bag to maintain the altitude of the bag, moving the gas confining bag in the atmosphere to a desired location, and removing the gas from the bag.

2. The method of claim 1 wherein the gas is moved into a large thin film plastic bag and confined in the plastic bag at substantially atmospheric pressure.

3. The method of claim 1 including controlling the supply of gas from the bag to the heating means in accordance with the ambient pressure.

4. The method of claim 1 wherein the gas is removed from the bag by withdrawing the gas under partial Vacuum into a gas receiving line.

5. An apparatus for transporting a mass of lighter than air gas, said gas being combustible including: a large gas impervious bag for confining a mass of lighter than air gas, a ballast unit attached to a portion of the bag for maintaining the upright position of the bag, said unit having a burner operable to heat the gas confined in the bag for maintaining the flight altitude of the bag, a container attached to the bag, a heat transfer medium located in said container in communication with the gas in the bag, said burner located outside the container and operable to heat the container, a control valve and a line connecting the valve to the bag and burner whereby gas in the bag is supplied to the burner, said control valve having a pressure control means operable to open the valve on an increase of pressure to provide the burner with a supply of gas.

6. The apparatus of claim 5 wherein said bag has a large generally spherical body and a downwardly converging funnel shaped neck.

7. The apparatus of claim 6 including a reinforcing band around the spherical body and tie-down lines secured to the band.

8. The apparatus of claim 5 wherein said bag is made of thin plastic film.

9. The apparatus of claim 5 wherein said bag has a downwardly extended neck having an opening, said ballast unit attached to the neck closing said opening.

10. An apparatus for transporting a mass of lighter than air gas including: a large gas impervious bag for confirming a mass of lighter than air gas, said bag having an opening in the lower portion thereof, a ballast unit attached to a portion of the bag, heat transfer means connected to the bag and in substantial surface contact with the gas confined in the bag, said heat transfer means closing said opening to prevent the escape of gas from the bag, and heating means outside the bag associated with heat transfer means to supply heat to heat transfer means to increase the temperature of the gas.

11. The apparatus of claim 10 wherein said heat transfer means comprises a container attached to the bag, a heat transfer medium located in said container in communication with gas in the bag, said heating means comprising a burner located outside the container and operable to heat the container.

12. The apparatus of claim 10 wherein: said gas confined in the bag is combustible and including means for carrying gas from the bag to the heating means whereby heating means is operable with gas from the bag.

13. The apparatus of claim 12 including: a control valve for controlling the supply of gas from the bag to the heating means, and the means for carrying the gas to the heating means comprised of a line connecting the valve to the bag and heating means.

14. The apparatus of claim 10 wherein: the heat transfer means includes a substance in contact with the gas in the bag, said substance normally in a liquid phase and changeable to a gas phase when subjected to heat generated by the heating means.

15. An apparatus for transporting a mass of combustible gas including: a large enclosed gas impervious bag for confining a mass of lighter than air gas, a ballast unit attached to a portion of the bag, heating means outside the bag, and means for carrying gas from the bag to the heating means whereby heating means is operable with gas from the bag.

References Cited UNITED STATES PATENTS 1,866,079 7/ 1932 Blondin 244-31 3,096,047 7/1963 Dunn 244-97 X 3,096,048 7/1963 Yost 24431 MILTON BUCHLER, Primary Examiner I. L. FORMAN, Assistant Examiner US. Cl. X.R. 244-97 

